Name:spoofing and masquerading

Creating false or misleading information in order to fool a
person or system into granting access or information not normally
available. Examples include operator spoofing to trick the operator into
making an error or giving away a password, location spoofing to trick a
person or system into believing a false location, login spoofing which
creates a fictitious login screen to get users to provide identification and
authentication information, email spoofing which forges email to generate
desired results, and time spoofing which creates false impressions of
relative or absolute time in order to gain advantage.

Complexity: Although
no deep mathematical analysis of this area has been published to date, it
appears that this issue does not involve any difficult mathematical
limitations. Limited results in providing secure channels have indicated
that such a process is not complex but that it may depend on cryptographic
techniques in some cases, which lead to substantial mathematical issues.
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